Originally from: The Guardian UK and tweaked for Australia audience by National Stroke Foundation.
What do the two readings mean?
Blood pressure is measured in “millimetres of mercury” (mm Hg) and is written as two numbers. The first (or top) number is your systolic blood pressure. It is the highest level your blood pressure reaches when your heart beats. The second (or bottom) number is your diastolic blood pressure. It is the lowest level your blood pressure reaches as your heart relaxes between beats.
How do I know if I have high blood pressure?
High blood pressure usually has no signs or symptoms, so the only way to know if you have hypertension is to have your blood pressure measured. The National Heart Foundation of Australia currently defines normal adult blood pressure as less than 120/80 mmHg. A reading between 120/80 and 140/90 mmHg is classified as normal to high blood pressure. High blood pressure is 140/90 mmHg or higher. If your blood pressure is 180/110 or higher, you have very high blood pressure.
If it has no symptoms why should I be concerned?
High blood pressure can lead to a heart attack, a stroke, heart failure or kidney disease.
There are often no symptoms of high blood pressure. Therefore, it is important that you have regular blood pressure checks. The only way to find out if your blood pressure is high is by having it checked regularly by a health professional.
Does blood pressure rise with age?
High blood pressure is caused by a range of factors including age, gender and family history. In most economically developed societies, blood pressure progressively rises with age although its unclear how much of this is to do with age per se or a lifetime of exposure to modifiable risk factors such as excessive salt and cholesterol intake, poor diet, physical inactivity and smoking.
Isn’t having a test quite anxiety-making?
Indeed. “White coat syndrome” is a phenomenon in which patients exhibit elevated blood pressure in a clinical setting but not at home. It is believed that this may be due to the anxiety some people experience when their reading is taken by a doctor.
To obtain a more accurate ambulatory reading, experts recommend that blood pressure should ideally be taken at home twice daily, once in the morning and once in the evening, with follow-up readings over several days.
One of my parents has high blood pressure: does that put me at risk?
Approximately 30% of cases of essential hypertension are attributable to genetic factors. For example, individuals who have one or two parents with hypertension are twice as likely to suffer from hypertension as the general population.
To date researchers have identified 28 blood pressure genes, including several that control a group of hormones known collectively as the angiotensin-renin-aldosterone system. This system influences all aspects of blood pressure control, including blood vessel contraction, sodium and water balance, and cell development in the heart. One theory as to why these genes may have been conserved in populations is that in times when salt was scarce, they conferred a survival advantage by enabling the body to conserve more sodium.